We propose to use a combination of two powerful techniques: aptamer selection (systematic evolution of ligands by exponential enrichment;SELEX) and in vitro compartmentalization (IVC), to develop a new method of generating libraries of functionalized nanoparticles and that can be screened directly for function. While the goal of this application is to develop a novel system for the direct identification of targeted nanoparticles which localize to human tumors, we will develop a platform technology which extends beyond the detection and treatment of cancer and other diseases and will result in the generation of a novel class of capture agents that will find use in a variety of applications and fields of research. PUBLIC HEALTH RELEVANCE: We are engineering a new platform technology that will be of great utility in a variety of different fields for diagnostic, therapeutic and research applications. We will use this technology to develop a new class of targeting agents that are specific for cancer cells.